1. Technical Field
The present invention relates to a processing device, an optical detection device, a display device, and so on.
2. Related Art
In the electronic devices such as a cellular phone a personal computer, a car navigation device, a ticket-vending machine, or a banking terminal, there is used in recent years a display device provided with a position detection function having a touch panel disposed on the front surface of the display section. According to the display device, it becomes possible for the user to point an icon or the like in a display image or input information while referring to the image displayed on the display section. As a position detection method using such a touch panel, there are known a resistive film type and a capacitance type, for example.
On the other hand, the display devices for projection display devices (projectors) and digital signage have a larger display area compared to the display devices for cellular phones and personal computers. Therefore, in these display devices, it is difficult to realize the position detection using the resistive touch panels and the capacitance touch panels described above.
Further, as the related art of the position detection device for the projection display devices, there are known the technologies disclosed in, for example, JP-A-11-345085 and JP-A-2001-142643. However, in the position detection devices, there arise the problems that the scale of the system becomes large and that the position detection is affected by the reflectance of the object.